True about peripheral chemoreceptors -

The peripheral chemoreceptors which regulate respiration are located in the carotid body and aortic bodies. These bodies are located in the connective tissue associated with the vessel wall, at the bifurcation of the common carotid, and on the arch of aorta, respectively. The characteristic cells of both these structures are called glomus cells. Type I glomus cells have a high dopamine content, which they possibly employ as a neurotransmetter. Peripheral chemoreceptors convey information to the DRG of neurons in medulla, for which purpose the afferent neurons from the carotid bodies pass through glossopharyngeal nerve and from the aortic bodies pass through vagus nerve. The most potent natural stimulus for peripheral chemoreceptors is low arterial PO2 (hypoxic hypoxia). The other stimuli which activate peripheral chemoreceptors are high arterial PCO2, and an increase in arterial hydrogen ion concentration (acidosis or low pH). The response to activation of peripheral chemoreceptors is an increase in pulmonary ventilation through an increase in the rate and depth of breathing.